Zymurgic Aura 2014

A wave of putrefaction surges from you, targeting creatures of your choice within a 30-foot radius around you, speeding the rate of decay in those it touches. The target must make a Constitution saving throw. It takes 10d6 necrotic damage on a failed save or half as much on a successful save. Its hit point maximum is reduced by an amount equal to the damage taken. This reduction lasts until the creature takes a long rest.